NATO chief: 'Ukraine has the momentum' in war, allies stand with Kyiv

NATO Secretary-General Jens Stoltenberg said on Tuesday that "Ukraine has the momentum" in the war with Russia and the Western defence alliance would stand with Kyiv as long as it takes.

"While Russia is increasingly resorting to horrific and indiscriminate attacks on civilians and critical infrastructure, President Putin is failing in Ukraine," Stoltenberg told a news conference on the eve of a meeting of NATO defence ministers in Brussels.

He said NATO would hold its annual nuclear deterrence exercise next week and was closely monitoring Russia's nuclear forces.

"We have not seen any changes in Russia's posture but we remain vigilant," he added.